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How are the current 8spds on 2021 trucks?


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In looking around at 2021 Sierra SLT 5.3s with X31, there are a lot that have the 8spd tranny installed instead of the 10spd. I’d prefer the 10 spd by far but it gets difficult to see online which trans it has due to GM’s piss-poor VIN build lookup. How are the 8spds now that the fluid was changed? Any anecdotals from current owners? Thanks

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I have a 2021 with an 8spd. I traded in a 2019 that also had the 8spd and it was a night and day difference. I would get all the usual 8spd complaints in the 19 but none of them in the 21. The only thing I can't comment on is if the 10spd shifts faster than the 8spd. I never drove a 10spd to compare it to

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In looking around at 2021 Sierra SLT 5.3s with X31, there are a lot that have the 8spd tranny installed instead of the 10spd. I’d prefer the 10 spd by far but it gets difficult to see online which trans it has due to GM’s piss-poor VIN build lookup. How are the 8spds now that the fluid was changed? Any anecdotals from current owners? Thanks
Didn't GMC downgrade all of 5.3 SLT's to the 8 speed late last year? According to the Build and Price site right now, 5.3 SLTs get the 8 speed but 6.2 and 3.0 diesels get the 10 speeds.

I would get the 6.2 or the 3.0 just to avoid the 8 speed.

Sent from my SM-G965U using Tapatalk

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I have a 2020 5.3 8 speed with approximately 30k miles on the odometer and it shifts smooth as butter since day 1.  8 speed issues were resolved in late 2019, dont hesitate on the 8 speed, its solid now.

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54 minutes ago, patrickjlindsay said:

Didn't GMC downgrade all of 5.3 SLT's to the 8 speed late last year? According to the Build and Price site right now, 5.3 SLTs get the 8 speed but 6.2 and 3.0 diesels get the 10 speeds.

I would get the 6.2 or the 3.0 just to avoid the 8 speed.

Sent from my SM-G965U using Tapatalk
 

Apparently is the case, but I thought they simply made the 10spd optional instead of standard with the 5.3. Thanks for all of the inputs, y’all..

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It was optional for a while. When I got my 21' you get 8 or 10 with the 5.3.

 

My 19's 8-speed was rough until they did a TSB on it, was smooth after that. 

The 10 speed certainly makes the truck feel faster though. 

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Cheap GM playing games with 3 different transmissions , SMH.  ( meanwhile the 10 speed is standard for all engines including their base engine on the Ford side)  I just don't get it 

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I had a 2020 loaner with an 8 speed last year. It was much smoother than my 2/2019 build RST 8 speed. 


I don't feel my 2019 8 speed is that terrible, but it does have some harsh or imbalanced shifts from time to time still (15K miles).

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My 2019 RST 8 speed, build date 3/19 shifts smooth as well.  Can’t feel the shifts.   1-2 is rough on cold mornings but apparently that’s a known issue and once it comes to op temp it is fine.  
 

I don’t know if they will add the 2021 to the attached bulletin or if there’s a updated bulletin. 

MC-10168176-9999.pdf

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I have a 2021 Silverado, 5.3, 8 speed, 4x4. At 500 miles I had hard downshifts into 1st gear at stop lights. It went away on the second day and was fine until  at 1200 miles the same thing happened  again and again at  1700 miles. Assembly date 9/30/1920 in Mexico. Do I qualify for a new transmission?

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46 minutes ago, dgstarr63 said:

I have a 2021 Silverado, 5.3, 8 speed, 4x4. At 500 miles I had hard downshifts into 1st gear at stop lights. It went away on the second day and was fine until  at 1200 miles the same thing happened  again and again at  1700 miles. Assembly date 9/30/1920 in Mexico. Do I qualify for a new transmission?

 

Not sure. Check out the article I posted. Maybe your symptoms are a reflection of what their talking about?

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13 hours ago, dgstarr63 said:

I have a 2021 Silverado, 5.3, 8 speed, 4x4. At 500 miles I had hard downshifts into 1st gear at stop lights. It went away on the second day and was fine until  at 1200 miles the same thing happened  again and again at  1700 miles. Assembly date 9/30/1920 in Mexico. Do I qualify for a new transmission?

No, separate issue altogether.  Change out your transmission fluid with the updated version and see if that helps.

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